Although the hydrated niobic acid is an unusual solid acid and making an impact onits application in catalysis, it is usually nonporous and has a rather low surface area andweak acidity upon heat treatment. To overcom...Although the hydrated niobic acid is an unusual solid acid and making an impact onits application in catalysis, it is usually nonporous and has a rather low surface area andweak acidity upon heat treatment. To overcome these shortcomings, the layered nio-bate had been pillared with thermostable inorganic oxides such as alumina and silica.Chromia is also a suitable inorganic oxide which can be used as pillar and contributesnew properties to the resultant materials. Here, we report the first synthesis of achromia-pillared layered niobate with porosity, acidity and thermostability.展开更多
The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The co...The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The complex has been characterized by elemental analysis,IR and NMR.The crystal structure of it has been determined by X-ray single crystal diffraction.And the results showed that the crystal belongs to triclinic system with space group P1and some crystal parameters:a=1.2202(9)nm,b=1.3158(10)nm,c=1.3804(10)nm,α=111.215(9)°,β=99.357(9)°,γ=96.075(10)°,V=2.006(2)nm 3,Z=1,F(000)=908,μ=1.489mm^(-1),D c=1.474g·cm^(-3),R_(1)=0.0375,wR_(2)=0.0839.The complex has a centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn_(2)O_(2)unit in which two bridged oxygen atoms both connect with an exo-cyclic tin atom which has a distorted octahedron.Each of the endo-cyclic tin atoms exhibits a distorted trigonal bipyramid coordination geometry with an additional weak coordination carboxylate oxygen.Four carboxylate ligands are divided into two types.And two of them are bidentate and connecting to each of exo-cyclic tin atoms by using both oxygen atoms,whereas the others bridge to each pair of exo-and endo-cyclic tin atoms utilizing one oxygen atom only.CCDC:220513.展开更多
L-（＋）-α-（positive butyl）-leucine ethyl ester bromide chiral ionic liquid was synthesized by using microwave-assisted synthesis method and L-（＋）-α-（positive butyl）-leucine ethyl ester terafluoroborate and h...L-（＋）-α-（positive butyl）-leucine ethyl ester bromide chiral ionic liquid was synthesized by using microwave-assisted synthesis method and L-（＋）-α-（positive butyl）-leucine ethyl ester terafluoroborate and hexafluorophosphate chiral ionic liquids were synthesized by the anion exchange reaction. The structures were characterized by IR, ~1HNMR and structure optimization calculation. The results of studies on physicochemical properties show that they possess better thermal stability, solubility, bio-solubility and high conductivity. They can serve as effective reaction media as well as chiral catalysts. They are presently being investigated as dispersion agents in molecular imprinting ployer.展开更多
Diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3), 2-ClC6H4CH2 (4), 4-ClC6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1∶1 mo-lar ratio in refluxin...Diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3), 2-ClC6H4CH2 (4), 4-ClC6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1∶1 mo-lar ratio in refluxing anhydrous benzene or toluene. They were characterized by elemental analysis, IR, 1H NMR and 119Sn NMR spectroscopy. And two sets of 119Sn chemical shifts were observed in the 119Sn NMR spectra of these compounds, indicating the presence of two types of environment around the tin atoms. The crystal structure of compound 1 was determined by X-ray single crystal diffraction analysis. The results showed that the crystal of com-pound 1 belongs to a monoclinic system with space group P21/c and unit cell dimensions: a=1.0718(9) nm, b=1.9666(17) nm, c=2.0480(17) nm, =96.4371(14)? Dc=1.450 g/cm3, Z=2, F(000)=1888, V=4.290(6) nm3, =1.206 mm-1, R1=0.0405, wR2=0.0786. The compound 1 belongs to centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn2O2 unit in which the bridging oxygen atoms are tri-coordinated. Each bridging oxygen atom also connects with an exo-cyclic tin atom. The endo- and exo-cyclic tin atoms are both five-coordinated, and have coordination geometry of distorted trigonal bipyramid.展开更多
A novel homologous series of 4'-methyoxyphenyl 4'-[(4-n-alkoxy-2,3,5,6-tetrafluoro-phenyl]benzyl ethers have been prepared via Pd-catalysed Heck reactions. Polarizing microscopic textural observation shows tha...A novel homologous series of 4'-methyoxyphenyl 4'-[(4-n-alkoxy-2,3,5,6-tetrafluoro-phenyl]benzyl ethers have been prepared via Pd-catalysed Heck reactions. Polarizing microscopic textural observation shows that these compounds exhibit enantiotropic nematic phases.展开更多
基金Project supported by the National Natural Science Foundation of China and the Natural Science Foundation of Jiangsu Province.
文摘Although the hydrated niobic acid is an unusual solid acid and making an impact onits application in catalysis, it is usually nonporous and has a rather low surface area andweak acidity upon heat treatment. To overcome these shortcomings, the layered nio-bate had been pillared with thermostable inorganic oxides such as alumina and silica.Chromia is also a suitable inorganic oxide which can be used as pillar and contributesnew properties to the resultant materials. Here, we report the first synthesis of achromia-pillared layered niobate with porosity, acidity and thermostability.
文摘The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The complex has been characterized by elemental analysis,IR and NMR.The crystal structure of it has been determined by X-ray single crystal diffraction.And the results showed that the crystal belongs to triclinic system with space group P1and some crystal parameters:a=1.2202(9)nm,b=1.3158(10)nm,c=1.3804(10)nm,α=111.215(9)°,β=99.357(9)°,γ=96.075(10)°,V=2.006(2)nm 3,Z=1,F(000)=908,μ=1.489mm^(-1),D c=1.474g·cm^(-3),R_(1)=0.0375,wR_(2)=0.0839.The complex has a centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn_(2)O_(2)unit in which two bridged oxygen atoms both connect with an exo-cyclic tin atom which has a distorted octahedron.Each of the endo-cyclic tin atoms exhibits a distorted trigonal bipyramid coordination geometry with an additional weak coordination carboxylate oxygen.Four carboxylate ligands are divided into two types.And two of them are bidentate and connecting to each of exo-cyclic tin atoms by using both oxygen atoms,whereas the others bridge to each pair of exo-and endo-cyclic tin atoms utilizing one oxygen atom only.CCDC:220513.
基金Funded by the National Natural Science Foundation of China(No.51433008)the Project of Scientific Research of Shaanxi(No.2017GY-182)the Science and Technology Fund Project
文摘L-（＋）-α-（positive butyl）-leucine ethyl ester bromide chiral ionic liquid was synthesized by using microwave-assisted synthesis method and L-（＋）-α-（positive butyl）-leucine ethyl ester terafluoroborate and hexafluorophosphate chiral ionic liquids were synthesized by the anion exchange reaction. The structures were characterized by IR, ~1HNMR and structure optimization calculation. The results of studies on physicochemical properties show that they possess better thermal stability, solubility, bio-solubility and high conductivity. They can serve as effective reaction media as well as chiral catalysts. They are presently being investigated as dispersion agents in molecular imprinting ployer.
基金Project supported by the National Natural Science Foundation of China (No. 20271025) and the Natural Science Foundation of Shandong Province (No. L2003B01).
文摘Diorganotin compounds {[R2Sn(ON=CHC6H5)]2O}2 [R=C6H5CH2 (1), 2-FC6H4CH2 (2), 4-FC6H4CH2 (3), 2-ClC6H4CH2 (4), 4-ClC6H4CH2 (5)] were synthesized by the reaction of R2SnO with HON=CHC6H5 in 1∶1 mo-lar ratio in refluxing anhydrous benzene or toluene. They were characterized by elemental analysis, IR, 1H NMR and 119Sn NMR spectroscopy. And two sets of 119Sn chemical shifts were observed in the 119Sn NMR spectra of these compounds, indicating the presence of two types of environment around the tin atoms. The crystal structure of compound 1 was determined by X-ray single crystal diffraction analysis. The results showed that the crystal of com-pound 1 belongs to a monoclinic system with space group P21/c and unit cell dimensions: a=1.0718(9) nm, b=1.9666(17) nm, c=2.0480(17) nm, =96.4371(14)? Dc=1.450 g/cm3, Z=2, F(000)=1888, V=4.290(6) nm3, =1.206 mm-1, R1=0.0405, wR2=0.0786. The compound 1 belongs to centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn2O2 unit in which the bridging oxygen atoms are tri-coordinated. Each bridging oxygen atom also connects with an exo-cyclic tin atom. The endo- and exo-cyclic tin atoms are both five-coordinated, and have coordination geometry of distorted trigonal bipyramid.
基金supported financially by the Advanced Material Research and Development Program of China.
文摘A novel homologous series of 4'-methyoxyphenyl 4'-[(4-n-alkoxy-2,3,5,6-tetrafluoro-phenyl]benzyl ethers have been prepared via Pd-catalysed Heck reactions. Polarizing microscopic textural observation shows that these compounds exhibit enantiotropic nematic phases.
